With the goal of providing single-stage-to-orbit capabilities that will enable spacecraft to take off and land like aircraft, and potentially ushering in an age of hypersonic air travel, Reaction Engines' Synergistic Air-Breathing Rocket Engine (SABRE) has the potential to be an aeronautical game-changer. Construction has now begun on the facility that will be used to conduct the ground test of SABRE's engine cycle.

Ground was broken on the new facility at Westcott Venture Park in Buckinghamshire, UK, last week. The site has a long history in rocket research, formerly being the home of the Rocket Propulsion Establishment, with engines for the Blue Streak missile and Black Arrow rockets both tested there. The goal is to have the new building ready for firing the engine core of the SABRE propulsion system in 2020.

UK-based Reaction Engines Ltd has been working on SABRE for a number of years, with the concept being independently reviewed by ESA in 2010. This led to a £60 million investment from the UK government to aid preparations for the design, manufacture and testing of a demonstrator engine, with ESA announcing its €10 million investment last year.

Key to the engine's design is the ability to use atmospheric air as an oxidizer after launch to negate the need for carrying onboard oxygen for the early part of its flight. This requires air scooped up for the atmosphere to be cooled from 1,000° C to -150° C within a hundredth of a second while avoiding ice forming. While testing of a prototype "precooler" to perform such a function was tested in 2012, a high temperature test of the precooler is planned for early 2018.

The precooler, engine core and thrust chamber form the three core building blocks of the SABRE, and Reaction Engines says all three can be validated using ground-based demonstrations to save time and money compared to flight tests. The company says it plans to independently develop these to maturity over the next four years, and the new test facility will obviously play a vital role in this.